- One tank is the **anode**, the other is the **cathode**.
- The **water** is like the lithium that moves back and forth.
💧 When you **charge** the battery, you **pump water uphill** into the anode tank.
⚡ When you **use** the battery, the water flows **downhill** back to the cathode.
The **height difference** between the two tanks is the **voltage** of the battery.
That's how much “push” the battery can give.
Each tank has its own **shape**. Some parts are wide (can hold a lot of water), some are narrow (hold less).
This shape is shown in the **dQ/dV plot**.
If we keep track of the height difference as the tanks fill and empty, we get the **OCV curve** — the battery’s special fingerprint.
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### ⚙️ The knobs you can play with:
- **SoC** → how full the tanks are right now
- **Vmin & Vmax** → the lowest and highest “water levels” we allow
- **NP ratio** → how big one tank is compared to the other
- **LiP ratio** → how much total water (lithium) is in the system
👉 Turn the knobs and watch how the tanks and the voltage curve change!